The permanent sutures that are used to flatten and tighten the abdominal wall are typically placed in the midline. The rectus abdominis muscles, prior to pregnancy, are lined up immediately side-by-side. Expansion of the abdominal wall during pregnancy allows the muscles to stretch apart, leaving a weak layer of fascia (connective tissue) spanning the gap between the two muscles – the medical term for which is diastasis. The midline tightening sutures correct the diastasis and bring the rectus muscles back into a 'side-by-side' configuration, flattening the abdominal wall in the process.
Although this midline tightening dramatically enhances the abdominal profile, it often does adequately address the fact that pregnancy can also wreak havoc on the waist, turning what was formerly an 'hourglass' figure into something that is more cylindrical in shape. For several years now I have been using permanent 'internal corset' sutures, placed laterally in the abdominal wall, that draw the waist inward and restore some of the hourglass effect of abdominal concavity at the waistline in frontal view. The addition of these sutures to midline tightening, and in some cases in place of midline tightening, has allowed me to achieve even more impressive postoperative results.